Joung Young Hee, Kim Hye Ryoun, Lee Mi Kyung, Park Ae Ja
Department of Laboratory Medicine, Chung-Ang University College of Medicine, 65-207, 3-Ka Hangang-Ro, Yongsan-Ku, Seoul 140-757, South Korea.
J Infect. 2007 May;54(5):504-8. doi: 10.1016/j.jinf.2006.09.016. Epub 2006 Nov 7.
Currently, antifungal drug susceptibility testing is labor-intensive, limited by delays in obtaining results and high costs. The purpose of this study was to determine the usefulness of flow cytometry (FCM) antifungal drug susceptibility testing as a routine laboratory procedure.
A total of 24 clinical isolates of Candida spp. and reference strains were tested for susceptibility to fluconazole by FCM using propidium iodide (PI) as an indicator of viability. The minimum inhibitory concentration (MIC) was defined as the lowest concentration of fluconazole that resulted in an increase of 30% in mean channel fluorescence (MCF), compared to the growth control. FCM results were compared with MIC results as determined by the Clinical and Laboratory Standards Institute (CLSI) method.
An 8h incubation was sufficient for determination of the MICs. The results by FCM at 8h and the NCCLS methods at 24h showed 87.5% agreement to within two drug dilutions. However, the FCM method is labor-intensive in proportion to the larger number of samples. For Candida lusitaniae, MICs by the FCM method showed poor correlation with the CLSI method.
Further evaluation is necessary to assess the usefulness of FCM as a technique for routine antifungal MIC testing in the clinical laboratory.
目前，抗真菌药敏试验劳动强度大，受结果获取延迟和成本高的限制。本研究的目的是确定流式细胞术（FCM）抗真菌药敏试验作为常规实验室程序的实用性。
使用碘化丙啶（PI）作为活力指标，通过FCM对总共24株念珠菌属临床分离株和参考菌株进行氟康唑药敏试验。最低抑菌浓度（MIC）定义为与生长对照相比，导致平均通道荧光（MCF）增加30%的氟康唑最低浓度。将FCM结果与临床和实验室标准协会（CLSI）方法测定的MIC结果进行比较。
8小时孵育足以确定MIC。FCM在8小时时的结果与NCCLS方法在24小时时的结果显示，在两种药物稀释度范围内一致性为87.5%。然而，FCM方法的劳动强度与样本数量成正比。对于葡萄牙念珠菌，FCM方法的MIC与CLSI方法的相关性较差。
有必要进一步评估FCM作为临床实验室常规抗真菌MIC检测技术的实用性。
